please advise on lap choice

[Giel]

It's been a while since I posted on the forum, but I just sold my old faceting machine and ordered a Scintillator 88. 
So I'm also buying new laps. (old laps are 6 inch) And I would really appreciate a bit of advice about certain laps!

I want to buy the following laps but am uncertian about the polish laps.

360 cheap chinese plated lap for preforming/rough cutting (36 dollar on ebay)
600 F dimafast plated lap for fine cutting. (can get it cheap from a local shop that hardly ever sells 8 inch laps)

For quartz I want to use:
1200 nubond for prepolish (yes I managed to get hold of a nubond lap)

creamway / greenway / darkside with oxide for polishing
Any advice on the three? I like the idea of an only add water lap like the creamway and greenway.
Is the polish quality of the three laps similar in terms of facet flatness and rounded facet edges?
Is one faster or slower then the others?

for other harder stones I want to use
3k diamond on a Batt lap for prepolish
100k diamond on a diamatrix lap for polish

can I also use the 3k on batt and 100k on diamatrix on stones like tourmaline?


Thanx in advance for the advice

[Aussie Sapphire]

The Creamway and Greenway laps are quite specific so best used if you have a lot of particular material.  The Darkside will be a lot more versatile.


Creamways are a zirconium charged lap so well suited for all quartz material - also good on peridot and beryls.  Brochure available here:
https://www.aussiesapphire.com.au/assets/brochures/767_6.pdf


Greenways are a chrome oxide charged lap so well suited for beryl - also good on other material such as quartz, tourmaline, garnet.


However, both are not general purpose laps - in contrast, the darkside is designed to be more flexible in that you use the polish best suited to the material (obviously a bit less convenient than a "just add water" lap).  Facet flatness should be reasonably similar across the three.


However, use of #100k on a diamatrix should also be suitable for all sorts of material such as tourmaline.


Others will hopefully have advice on cutting lap choice and differences between polish laps.


cheers Leah

[Giel]

Thanx a lot for the reply Leah!

It's difficult choosing laps if you are an "isolated cutter" and cannot try out machines and laps somewhere!
There is a lapidary shop in my city, the guy does facet stones. He's very experienced with cutting but he's using and selling laps from the seventies!
He has not even heard of the gearloose products....so he will advize tin laps, copper laps, ultra laps on plexiglass and the like....

But my plan about the laps is already down the drain because the 600 dimafast he had is a rippled / channel disc with grooves, so I declined.
And he did not want to sell me the nubond, since  he has only a few nubond laps left.

I will probably be cutting a lot of quartz for starters because I have not much cash left for rough after buying a new machine and laps.
I also have some rough tourmaline and garnet lying around so maybe a greenway for now just to get cutting.
I am not sure yet.

I will be using the diamatrix for polishing harder stones in the end as well. And will buy it for sure since i read so many good reviews about them.

I am considering buying a 600 sintered lap, When I take in account shipping costs, import tax, customs handling fees, EU-fees, the price difference between sintered and a good plated lap is not so big.

So I will probably start with

360 cheap plated lap
600 sintered lap
3k on batt
diamatrix & greenway/darkside

Does 3k on batt work well on all stones? I read that a lot of people love their 3k on batt lap.

[MakkyBrown]

Giel, I use a 800 sintered, and polish with 100k on a 100% tin lap. I knurl the tin lap every time I load it.

[Faceting Frank]

Hi Giel, thanks for the comment on my faceting machine.
3k on Batt laps produces a brilliant pre-polish on those stones you normally polish with diamond. Like C Z, Corundum, Spinel etc. I use diamond powder with a couple of drops of baby oil at 300rpm. I don’t bother with Diasticks they are too slow.
 So good a finish in fact I polish those stones with 60k on a stationary Batt lap, small facets will be polished with just a couple of wipes.

[Giel]

Giel, I use a 800 sintered, and polish with 100k on a 100% tin lap. I knurl the tin lap every time I load it.

yeah I would love to have one of those sintered wheels from Gempro, but they are out of stock and hard to find if you are in europe.

Hi Giel, thanks for the comment on my faceting machine.
3k on Batt laps produces a brilliant pre-polish on those stones you normally polish with diamond. Like C Z, Corundum, Spinel etc. I use diamond powder with a couple of drops of baby oil at 300rpm. I don’t bother with Diasticks they are too slow.
 So good a finish in fact I polish those stones with 60k on a stationary Batt lap, small facets will be polished with just a couple of wipes.

I have never worked on a batt before as they dont sell them here, only place I found them is somewhere in france for a whopping 265 euro's....
I will probably end up ordering one from the states.

[Faceting Frank]

Where do you live Giel?

[Giel]

The Netherlands

It's just that there is not much traffic on EU forums about faceting, and I like the people on this forum.

[Bucket]

Thanks Giel, but let's face it, what's not to like? We are a friendly bunch.

[FlashGP]

Ah, well then you'll have plenty of time over winter to  use your new machine and finish your concave cutter :-)

[Giel]

Thanks Giel, but let's face it, what's not to like? We are a friendly bunch.

Yes a friendly bunch, and more than willing to help out! 

Ah, well then you'll have plenty of time over winter to  use your new machine and finish your concave cutter :-)

Yeah, I hope the machine will arrive soon, had contact with Zane from polymetric, he explained they have a lot of orders at the moment, so it will take some time for him to build it. In the meantime I am ordering laps and slowly progressing on the concave cutter.
I think I will make the concave cutter more basic for now, so I will only have the option of cutting on cylindrical mandrels, just so I can get cutting. I can always modify it later on to use it with a V-wheel.

I have also made a choice on the laps, For now I will order a Batt lap for prepolish, and a diamatrix and darkside for polish.
A 360 cheap chinese lap for preforming, and I am trying to get a hold of those australian made sintered laps, If I cannot find it, I will buy the cheap chinese laps for now.

Thanx you all for the input!

[Dihusky]

Hi Geil, you had some good suggestions so far, so to add my two bobs worth, my methodology is rough on a 250 or finer frisby lap on a quality master then 1200 frisby, 3000 or 8000 on copper for pre-polish and I finish with 60k on tin, I don't use any synthetics or pre-mixes, just de-Beers diamond and baby oil.

Where I start will always depend on the size of the rough, on smaller stones I'll often start with a 600 or 800 then go straight to 8000 and polish. Another trick is to prime the 8000 on copper, cut with a slow water drip making sure there is no soap in the water, keeps the stone cool and washes the debris off, works remarkably well with a mature lap.

My reasoning with copper as pre-polish is I can re-dress easily to ensure it stays absolutely flat so when I move to final polish the facets polish up very quickly with zero cheating. The copper pre-polish 'trues' up the facets as they are often slightly out coming off a frisby.

Another lap with an excellent reputation is the CAT lap, made by Horst Ricker in Rubyvale, never used one myself but know plenty who do and speak highly of them.

As for the Gempro sintered laps, the guy who used to make them has stopped manufacturing laps, I purchased one of his very last batch.

Good luck with the Scintillator, would love to get one but the $AUS is so weak, I can't justify $9k!!!

[Pro-oz]

I'm with Dihusky, pre polish on copper and polish on tin and will probably never change. I must give the slow water drip on copper a try. Thanks for posting that little tip Dihusky.

Cheers Prooz.

[FlashGP]

I have been cutting and prepolishing using  3000 and 8000 on zinc, it is a little more aggressive tha n copper.

I have found a water drip works really well on both when prepolishing thr Quartz family, but Topaz and harder stones prefer an oil based lubricant.  Even Snale Oil  was too thin for a piece of Topaz I recently cut.  I had to thicken it with a couple of drops of 3 in 1 oil on my charging/cleaning facewipe.

Regards
Flash

[Giel]

So many options for polish and pre-polish, in the end I will just have to try different laps for different stones, and see what works for me. And most of all get more experience.
I have been faceting on my old machine for a few years so I dont have to start from scratch.

Good thing is, I can always ask on the forum if I run into problems!